Garlic and onions: their cancer prevention properties

Allium Sativum Methanolic Extract (garlic) Improves Therapeutic Efficacy of Albendazole Against Hydatid Cyst: In Vivo Study

After gas chromatography and mass spectrometry of prepared methanolic extract of Allium sativum, 40 laboratory BALB/c mice were infected intraperitoneally by injection of 1,500 viable protoscoleces. Five months after infection, the infected mice were allocated into four treatment groups, including 1- Albendazole (100 mg/kg); 2- Allium sativum methanolic extract (10 mL/L); 3- A. sativum methanolic extract (10 mL/L) + Albendazole (50 mg /kg); and 4- untreated control group. After 30 days of daily treatment, total number and weight of cysts and size of the largest cyst as well as blood serum bilirubin and liver enzymes were compared between the mice of different groups.The total number and weight of cysts and size of the largest cyst were significantly lower in treated groups A. sativum 10 mL/L + Albendazole 50 and Albendazole 100 in comparison to those of the control group (p < 0.05).The activity of alanine aminotransferase (ALT) enzyme and bilirubin concentration were significantly lower in the mice treated with A. sativum 10 mL/L and A. sativum 10 mL/L + Albendazole 50, when compared to the control group. In addition, bilirubin concentration revealed significant decrease in A. sativum 10 mL/L and A. sativum 10 mL/L + Albendazole 50 groups, when compared to the Albendazole group. In conclusion, administration of A. sativum 10 mL/L improved the anti-hydatidosis activity of Albendazole 50 mg /kg, due to parasitological effects similar to Albendazole 100 mg /kg but less hepatotoxic effects.

Garlic intake and gastric cancer risk: Results from two large prospective US cohort studies

Although many case-control studies suggested that garlic intake may reduce gastric cancer risk, evidence from prospective cohort studies has been lacking. We examined the association between garlic intake and subsequent risk of gastric cancer among 77,086 women in the Nurses' Health Study (1984-2014) and 46,398 men in the Health Professionals Follow-Up Study (1986-2014). Relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards models. We additionally examined garlic intake in relation to Helicobacter pylori (H. pylori) infection among 613 participants using logistic regression. During up to 30 years of follow-up, 292 participants were diagnosed with gastric cancer. The pooled multivariable RR of gastric cancer among participants who ate garlic, as compared to those who did not, were 1.11 (95% CI = 0.81-1.51) for the intake of garlic less than once per week, 0.98 (95% CI = 0.71-1.36) for one to four times per week and 1.39 (95% CI = 0.89-2.17) for five or more times per week (p for trend = 0.23). Similarly, no statistically significant association was observed cross-sectionally between garlic intake and H. pylori infection (comparing five or more times per week to never, pooled multivariable odds ratio = 1.66, 95% CI = 0.89-3.09; p for trend = 0.11). The findings from this large prospective study do not support the hypothesis that high garlic intake reduces risk of gastric cancer.

Allium vegetable intakes and the incidence of cardiovascular disease, hypertension, chronic kidney disease, and type 2 diabetes in adults: a longitudinal follow-up study

OBJECTIVES

This study investigated the association between habitual consumption of allium vegetables (garlic and onion) and the incidence of cardiovascular disease (CVD) outcomes, hypertension (HTN), chronic kidney disease (CKD), and type 2 diabetes (T2D).

METHODS

Adult men and women, participated in the Tehran Lipid and Glucose Study (2006-2008 to 2012-2014), were recruited. Habitual dietary intakes were assessed using a validated semiquantitative food frequency questionnaire. Demographics, anthropometrics, blood pressure, and biochemical variables were evaluated at baseline and during follow-up examinations. Multivariate Cox proportional hazard regression models adjusted for potential confounders were used to estimate the development of CVD outcomes, HTN, CKD, and T2D in relation to allium vegetable intakes.

RESULTS

Mean age of participants (44.2% men) was 40.3 ± 14.3 years, at baseline. During an average of 6 years of follow-up, the incidence rate of CVD outcomes, HTN, CKD, and T2D were 3.3, 15.5, 17.9, and 6.7%, respectively. A higher habitual intake of allium vegetables was associated with a 64% reduced risk of CVD outcomes (hazard ratio = 0.36, 95% confidence interval, CI = 0.18-0.71; P for trend = 0.011), 32% lower incidence of CKD (hazard ratio = 0.69, 95% CI = 0.46-0.98; P for trend = 0.11), and 26% decreased HTN development (hazard ratio = 0.74, 95% CI = 0.54-1.00; P for trend = 0.06). No significant association was observed between allium vegetable intakes and the risk of T2D. Allium vegetable intake was related to 6 years' changes of triglyceride levels (β = -0.81, P = 0.01) and creatinine clearance (β = 0.56, P = 0.01).

CONCLUSION

Data of the current study support the available mechanistic findings regarding cardiorenal protective properties of allium vegetables.

The contribution of alliaceous and cruciferous vegetables to dietary sulphur intake

Despite its importance in many areas of human metabolism, there are no recommended daily intake guide lines for sulphur. It is generally assumed that most dietary sulphur originates from intake of methionine and cysteine. We estimated sulphur intake from food diaries, and validated the results with the use of a duplicate diet analyses. Sulphur intake estimations were highly correlated with that obtain through an elemental analysis of duplicate diets, with a mean±sd daily intakes of 956±327.9mg estimated from diet diary analyses and 935±329.9mg estimated by a duplicate diet analyses. Sulphur intake from alliaceous and cruciferous vegetables contributed up to 42% of total sulphur intake. Daily intake estimation comparisons through diet diary analyses and duplicate diet for other elements showed good agreement, except for sodium and zinc, in which analyses of 24h diet dairies overestimated intake by 35% and 52%, respectively.

Hydrogen Sulfide: A Worthwhile Tool in the Design of New Multitarget Drugs

H₂S is a gaseous molecule able to trigger a plethora of central physiological and pharmacological effects as antioxidant, pro- and anti-inflammatory, pro- and anti-nociceptive, neuromodulator, and cytoprotective. The polypharmacology of H₂S depends on the wide variety of targets implicated, but, despite the efforts, the mechanisms of action that should clarify its activity are still not completely unrevealed. Nevertheless, many attempts to exploit the multifaceted profile of this molecule have already been accomplished and many chemical entities containing an H₂S-releasing pharmacophore have been synthetized. Here we discuss recent investigations on multitarget molecules able to release H₂S, with a particular focus on the combinations of "native drug" with moieties structurally able to release H₂S and their applications as therapeutic tools in bone disease, gastrointestinal system and neurodegenerative disorders.

Herbal approach in the treatment of pancytopenia

Pancytopenia is a health condition in which there is a reduction in the amount of leucocytes, erythrocytes and thrombocytes. If more than one of the blood cells is low then the condition is called as bicytopenia. The pancytopenic condition is observed in treatment of diseased conditions like thalassemia and hepatitis C. Iatrogenically pancytopenia is caused by some antibiotics and anti-HCV drugs. Medical conditions like aplastic anaemia, lymphoma, copper deficiency, and so forth can also cause pancytopenia. Pancytopenia can in turn decrease the immunity of the person and thereby can be fatal. Current therapies for pancytopenia include bone marrow stimulant drugs, blood transfusion and bone marrow transplant. The current therapies are very excruciating and have long-term side-effects. Therefore, treating these condition using herbal drugs is very important. Herbs like wheatgrass, papaya leaves and garlic are effective in treating single lineage cytopenias. The present review is focused on the potential effects of natural herbs for the treatment of pancytopenia.

The Cytotoxicity of the Ajoene Analogue BisPMB in WHCO1 Oesophageal Cancer Cells Is Mediated by CHOP/GADD153

Garlic is a food and medicinal plant that has been used in folk medicine since ancient times for its beneficial health effects, which include protection against cancer. Crushed garlic cloves contain an array of small sulfur-rich compounds such as ajoene. Ajoene is able to interfere with biological processes and is cytotoxic to cancer cells in the low micromolar range. BisPMB is a synthetic ajoene analogue that has been shown in our laboratory to have superior cytotoxicity to ajoene. In the current study we have performed a DNA microarray analysis of bisPMB-treated WHCO1 oesophageal cancer cells to identify pathways and processes that are affected by bisPMB. The most significantly enriched biological pathways as assessed by gene ontology, KEGG and ingenuity pathway analysis were those involving protein processing in the endoplasmic reticulum (ER) and the unfolded protein response. In support of these pathways, bisPMB was found to inhibit global protein synthesis and lead to increased levels of ubiquitinated proteins. BisPMB also induced alternate splicing of the transcription factor XBP-1; increased the expression of the ER stress sensor GRP78 and induced expression of the ER stress marker CHOP/GADD153. CHOP expression was found to be central to the cytotoxicity of bisPMB as its silencing with siRNA rendered the cells resistant to bisPMB. The MAPK proteins, JNK and ERK1/2 were activated following bisPMB treatment. However JNK activation was not critical in the cytotoxicity of bisPMB, and ERK1/2 activation was found to play a pro-survival role. Overall the ajoene analogue bisPMB appears to induce cytotoxicity in WHCO1 cells by activating the unfolded protein response through CHOP/GADD153.

Arsenic-induced stress activates sulfur metabolism in different organs of garlic (Allium sativum L.) plants accompanied by a general decline of the NADPH-generating systems in roots

Arsenic (As) contamination is a major environmental problem which affects most living organisms from plants to animals. This metalloid poses a health risk for humans through its accumulation in crops and water. Using garlic (Allium sativum L.) plants as model crop exposed to 200μM arsenate, a comparative study among their main organs (roots and shoots) was made. The analysis of arsenic, glutathione (GSH), phytochelatins (PCs) and lipid peroxidation contents with the activities of antioxidant enzymes (catalase, superoxide dismutase, ascorbate-glutathione cycle), and the main components of the NADPH-generating system, including glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), NADP-malic enzyme (NADP-ME) and NADP-isocitrate dehydrogenase (NADP-ICDH) was carried out. Data showed a correlation among arsenic accumulation in the different organs, PCs content and the antioxidative response, with a general decline of the NADPH-generating systems in roots. Overall, our results demonstrate that there are clear connections between arsenic uptake, increase of their As-chelating capacity in roots and a decline of antioxidative enzyme activities (catalase and the ascorbate peroxidase) whose alteration provoked As-induced oxidative stress. Thus, the data suggest that roots act as barrier of arsenic mediated by a prominent sulfur metabolism which is characterized by the biosynthesis of high amount of PCs.

EGFR gene regulation in colorectal cancer cells by garlic phytocompounds with special emphasis on S-Allyl-L-Cysteine Sulfoxide

Colorectal cancer is one among the most common cancers in the world and a major cause of cancer related deaths. Similar to other cancers, colorectal carcinogenesis is often associated with over expression of genes related to cell growth and proliferation, especially Epidermal Growth Factor Receptor (EGFR). There is an increasing attention towards the plant derived compounds in prevention of colorectal carcinogenesis by downregulating EGFR. Among plants, garlic (Allium sativum L.) is emerging with anticancer properties by virtue of its organosulfur compounds. The present study was aimed to analyze the interaction ability of garlic compounds in the active region of EGFR gene by in silico molecular docking studies and in vitro validation. This was conducted using the Discovery studio software version 4.0. Among the tested compounds, s-allyl-l-cysteine-sulfoxide (SACS)/alliin showed higher affinity towards EGFR. Furthermore, wet lab analysis using cell viability test and EGFR expression analysis in colorectal cancer cells confirmed its efficacy as a potent anticancer agent.

Diet and biliary tract cancer risk in Shanghai, China

Trends in biliary tract cancer incidence rates have increased in Shanghai, China. These trends have coincided with economic and developmental growth, as well as a shift in dietary patterns to a more Westernized diet. To examine the effect of dietary changes on incident disease, we evaluated associations between diet and biliary tract cancers amongst men and women from a population-based case-control study in Shanghai, China. Biliary tract cancer cases were recruited from 42 collaborating hospitals in urban Shanghai, and population-based controls were randomly selected from the Shanghai Household Registry. Food frequency questionnaire data were available for 225 gallbladder, 190 extrahepatic bile duct, and 68 ampulla of Vater cancer cases. A total of 39 food groups were created and examined for associations with biliary tract cancer. Interestingly, only four food groups demonstrated a suggested association with gallbladder, extrahepatic bile duct, or ampulla of Vater cancers. The allium food group, consisting of onions, garlic, and shallots showed an inverse association with gallbladder cancer (OR: 0.81, 95% CI: 0.68-0.97). Similar trends were seen in the food group containing seaweed and kelp (OR: 0.79, 95% CI: 0.67-0.96). In contrast, both preserved vegetables and salted meats food groups showed positive associations with gallbladder cancer (OR:1.27, 95% CI: 1.06-1.52; OR: 1.18, 95% CI: 1.02-1.37, respectively). Each of these four food groups showed similar trends for extrahepatic bile duct and ampulla of Vater cancers. The results of our analysis suggest intake of foods with greater anti-inflammatory properties may play a role in decreasing the risk of biliary tract cancers. Future studies should be done to better understand effects of cultural changes on diet, and to further examine the impact diet and inflammation have on biliary tract cancer incidence.

Chemical Composition and Biological Activity of Allium cepa L. and Allium × cornutum (Clementi ex Visiani 1842) Methanolic Extracts

Here, we report a comparative study of the phytochemical profile and the biological activity of two onion extracts, namely Allium cepa L. and Allium × cornutum (Clementi ex Visiani 1842), members of the family Amaryllidaceae. The identification of flavonoids and anthocyanins, and their individual quantities, was determined by high-performance liquid chromatography (HPLC). The potency of both extracts to scavenge free radicals was determined by the DPPH (2,2'-diphenyl-1-picrylhydrazyl) radical-scavenging activity and oxygen radical absorbance capacity (ORAC) methods. The DNA protective role was further tested by the single-cell gel electrophoresis (COMET) assay and by Fenton's reagent causing double-strand breaks on the closed circular high copy pUC19 plasmid isolated from Escherichia coli. In the presence of both extracts, a significant decrease in DNA damage was observed, which indicates a protective role of Allium cepa and Allium × cornutum on DNA strand breaks. Additionally, cytotoxicity was tested on glioblastoma and breast cancer cell lines. The results showed that both extracts had antiproliferative effects, but the most prominent decrease in cellular growth was observed in glioblastoma cells.

Spices for Prevention and Treatment of Cancers

Spices have been widely used as food flavorings and folk medicines for thousands of years. Numerous studies have documented the antioxidant, anti-inflammatory and immunomodulatory effects of spices, which might be related to prevention and treatment of several cancers, including lung, liver, breast, stomach, colorectum, cervix, and prostate cancers. Several spices are potential sources for prevention and treatment of cancers, such as Curcuma longa (tumeric), Nigella sativa (black cumin), Zingiber officinale (ginger), Allium sativum (garlic), Crocus sativus (saffron), Piper nigrum (black pepper) and Capsicum annum (chili pepper), which contained several important bioactive compounds, such as curcumin, thymoquinone, piperine and capsaicin. The main mechanisms of action include inducing apoptosis, inhibiting proliferation, migration and invasion of tumors, and sensitizing tumors to radiotherapy and chemotherapy. This review summarized recent studies on some spices for prevention and treatment of cancers, and special attention was paid to bioactive components and mechanisms of action.

Cinnamomum verum component 2-methoxycinnamaldehyde: a novel antiproliferative drug inducing cell death through targeting both topoisomerase I and II in human colorectal adenocarcinoma COLO 205 cells

BACKGROUND

Cinnamomum verum is used to manufacture the spice cinnamon. In addition, the plant has been used as a Chinese herbal medication.

METHODS

We investigated the antiproliferative effect of 2-methoxycinnamaldehyde (2-MCA), a constituent of the cortex of the plant, and the molecular biomarkers associated with tumorigenesis in human colorectal adenocarcinoma COLO 205 cells. Specifically, cell viability was evaluated by colorimetric assay; apoptosis was determined by flow cytometry and morphological analysis with bright field, acridine orange, and neutral red stainings, as well as comet assay; topoisomerase I activity was determined by assay based upon DNA relaxation and topoisomerase II by DNA relaxation plus decatentation of kinetoplast DNA; lysosomal vacuolation and volume of acidic compartments (VACs) were determined by neutral red staining.

RESULTS

The results demonstrate that 2-MCA inhibited proliferation and induced apoptosis as implicated by mitochondrial membrane potential (ΔΨm) loss, activation of both caspase-3 and -9, increase of annexin V(+)PI(+) cells, as well as morphological characteristics of apoptosis. Furthermore, 2-MCA also induced lysosomal vacuolation with elevated VAC, cytotoxicity, and inhibitions of topoisomerase I as well as II activities. Additional study demonstrated the antiproliferative effect of 2-MCA found in a nude mice model.

CONCLUSIONS

Our data implicate that the antiproliferative activity of 2-MCA in vitro involved downregulation of cell growth markers, both topoisomerase I and II, and upregulation of pro-apoptotic molecules, associated with increased lysosomal vacuolation. In vivo 2-MCA reduced the tumor burden that could have significant clinical impact. Indeed, similar effects were found in other tested cell lines, including human hepatocellular carcinoma SK-Hep-1 and Hep 3B, lung adenocarcinoma A549 and squamous cell carcinoma NCI-H520, and T-lymphoblastic MOLT-3 (results not shown). Our data implicate that 2-MCA could be a potential agent for anticancer therapy.

Garlic oil polysulfides: H2S- and O2-independent prooxidants in buffer and antioxidants in cells

The health benefits of garlic and other organosulfur-containing foods are well recognized and have been attributed to both prooxidant and antioxidant activities. The effects of garlic are surprisingly similar to those of hydrogen sulfide (H2S), which is also known to be released from garlic under certain conditions. However, recent evidence suggests that polysulfides, not H2S, may be the actual mediator of physiological signaling. In this study, we monitored formation of H2S and polysulfides from garlic oil in buffer and in human embryonic kidney (HEK) 293 cells with fluorescent dyes, 7-azido-4-methylcoumarin and SSP4, respectively and redox activity with two redox indicators redox-sensitive green fluorescent protein (roGFP) and DCF. Our results show that H2S release from garlic oil in buffer requires other low-molecular-weight thiols, such as cysteine (Cys) or glutathione (GSH), whereas polysulfides are readily detected in garlic oil alone. Administration of garlic oil to cells rapidly increases intracellular polysulfide but has minimal effects on H2S unless Cys or GSH are also present in the extracellular medium. We also observed that garlic oil and diallyltrisulfide (DATS) potently oxidized roGFP in buffer but did not affect DCF. This appears to be a direct polysulfide-mediated oxidation that does not require a reactive oxygen species intermediate. Conversely, when applied to cells, garlic oil became a significant intracellular reductant independent of extracellular Cys or GSH. This suggests that intracellular metabolism and further processing of the sulfur moieties are necessary to confer antioxidant properties to garlic oil in vivo.

Raw Garlic Consumption and Lung Cancer in a Chinese Population

BACKGROUND

Evidence of anticancer properties of garlic for different cancer sites has been reported previously in in vitro and in vivo experimental studies but there is limited epidemiologic evidence on the association between garlic and lung cancer.

METHODS

We examined the association between raw garlic consumption and lung cancer in a case-control study conducted between 2005 and 2007 in Taiyuan, China. Epidemiologic data was collected by face-to-face interviews from 399 incident lung cancer cases and 466 healthy controls. We used unconditional logistic regression models to estimate crude and adjusted ORs (aOR) and their 95% confidence intervals (CI). Adjusted models controlled for age, sex, average annual household income 10 years ago, smoking, and indoor air pollution.

RESULTS

Compared with no intake, raw garlic intake was associated with lower risk of development of lung cancer with a dose-response pattern (aOR for <2 times/week = 0.56; 95% CI, 0.39-0.81 and aOR for ≥2 times/week = 0.50; 95% CI, 0.34-0.74; Ptrend = 0.0002). Exploratory analysis showed an additive interaction of raw garlic consumption with indoor air pollution and with any supplement use in association with lung cancer.

CONCLUSIONS

The results of the current study suggest that raw garlic consumption is associated with reduced risk of lung cancer in a Chinese population.

IMPACT

This study contributes to the limited research in human population on the association between garlic and lung cancer and advocates further investigation into the use of garlic in chemoprevention of lung cancer. Cancer Epidemiol Biomarkers Prev; 25(4); 624-33. ©2016 AACR.

Effect of Dietary Processed Sulfur Supplementation on Water-holding Capacity, Color, and Lipid Profiles of Pork

This study was performed to investigate the effect of dietary processed sulfur supplementation on water-holding capacity, color, and lipid profiles of pork according to the level of dietary processed sulfur (0%, CON; 0.3%, S). The pigs were slaughtered at an average final weight of 120 kg, and the longissimus dorsi muscles were collected from the carcasses. As results, pork processed with sulfur had significantly higher moisture and ash contents compared to those of CON but lower crude fat, pH, expressible drip, lower redness and yellowness, and greater lightness. Pork processed with sulfur showed significantly lower total lipid content, triglycerides, and atherosclerosis index but significantly higher high-density lipoprotein cholesterol. Feeding processed sulfur significantly lowered myristic acid, heptadecanoic acid, and stearic acid contents, whereas monounsaturated fatty acids and oleic acids were significantly higher compared to those in the CON. Higher amounts of polyunsaturated fatty acids and n-6 fatty acids were observed in the pork processed with sulfur than that of the CON. Therefore, supplementing pigs with dietary sulfur improved nutrient and meat quality.